With low-viscosity media (such as, for example, water and of oils), the measuring of fill levels is frequently performed mechanically using a so-called float switch. In contrast, with high-viscosity media (such as, for example, fluid greases) an electronically working capacitive sensor is often used.
It is also technically possible to measure a fill level of oil with a capacitive sensor; however for cost reasons this is impractical with presently available sensors. Disadvantageously, therefore, different sensor types must be used to measure the fill levels of different mediums. This leads to a high number of variants, which in turn incurs costs.
Here the capacitive sensors available to date are constructed in part relatively complex and thus not very compact. Furthermore, they are expensive.